Gary C
Veteran Member
The CAL socket has a 3 volt peak to peak square waveform at 2kHZ. Touch your probe to the contact in the centre and adjust time base and amplitude to get a good image. Its a good way to get to know your scope.
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Macintosh classic ii vertical collapse
- Thread starter Lololobolosse
- Start date
The CAL socket has a 3 volt peak to peak square waveform at 2kHZ. Touch your probe to the contact in the centre and adjust time base and amplitude to get a good image. Its a good way to get to know your scope.
Lololobolosse
Experienced Member
- Joined
- Oct 29, 2021
- Messages
- 88
This is the best i could do so far, i watched some videos in the past but this is my 1st time really using a scope.
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What type of probe are you using? x1, x10, x100? If you put all knobs into the CAL position (they should click or push in), you should get a signal three divisions (squares) high depending on the setting (1V, .1V / div, 10mV / div). On an x1 probe, 1V/div should result in three divisions of amplitude (divide or multiply otherwise). If it doesn't match, you might need to clean/excercise your scope's switches and connectors or there could be some other faults.
Gary C
Veteran Member
I 'think' its showing a square wave but part of it isn't bright enough to see. Adjust FOCUS & INTENS to see if you can get a continuous trace
Turn the Time/div on MAIN TB anticlock wise and you should get less waveforms on the screen
The four main knobs have a little centre knob that allows fine adjustment, but all should be turned to the CAL position to make them read right.
Turn the Time/div on MAIN TB anticlock wise and you should get less waveforms on the screen
The four main knobs have a little centre knob that allows fine adjustment, but all should be turned to the CAL position to make them read right.
Gary C
Veteran Member
With a signal of 2khz each wave should repeat every 0.0005 of a second, or 0.5 milliseconds.
With the CAL knob turned until it clicks at the CAL position and the main control set at .5 ms, each wave should fit in one horizontal graduation on the display
Its a 3V signal so with the outer knob clicked to 1 V/DIV it should, with CAL rotated until it clicks at the CAL position, should cover 3 graduations on the display. However some probes allow you to select X1 & X10 (or more) and this reduces the signal such that if set to X10, you will only fill 0.3 of a graduation rather than 3 of them
Play around with the AMPL controls & MAIN TB and see the effects
Things to note
at the top of the scope you have three buttons and you have MAIN TB pushed in, this means the trace is controlled by the MAIN TB (TB means TIme Base) which is fine for now
on main time base control you have three more buttons AUTO TRIG SINGLE. These determine how the trace is Triggered or what causes the beam to scan across the screen. AUTO trigger is fine for now, but adjusting level may sometimes be necessary to get a stable trace.
At the bottom of this section, you have four buttons A B EXT MAINS. These select where the trigger (ie what starts the trace moving) comes from. Selected to A means the display is triggered from the signal you are currently measuring on input A. Selected to B would mean it would trigger the display on a signal on B (which might be useful if you wanted to see what was happening on input A, every time input B did something). EXT just means you can inject a third signal on the EXT connector, but you wont see it on the screen.
Lots more to discuss about scopes, but thats probably enough to be going on with
Please, ask questions
To me, a scope is the single most important tool this side of a screwdriver, but it is a tool and can tell you what you want to see if you dont use it and understand it.
With the CAL knob turned until it clicks at the CAL position and the main control set at .5 ms, each wave should fit in one horizontal graduation on the display
Its a 3V signal so with the outer knob clicked to 1 V/DIV it should, with CAL rotated until it clicks at the CAL position, should cover 3 graduations on the display. However some probes allow you to select X1 & X10 (or more) and this reduces the signal such that if set to X10, you will only fill 0.3 of a graduation rather than 3 of them
Play around with the AMPL controls & MAIN TB and see the effects
Things to note
at the top of the scope you have three buttons and you have MAIN TB pushed in, this means the trace is controlled by the MAIN TB (TB means TIme Base) which is fine for now
on main time base control you have three more buttons AUTO TRIG SINGLE. These determine how the trace is Triggered or what causes the beam to scan across the screen. AUTO trigger is fine for now, but adjusting level may sometimes be necessary to get a stable trace.
At the bottom of this section, you have four buttons A B EXT MAINS. These select where the trigger (ie what starts the trace moving) comes from. Selected to A means the display is triggered from the signal you are currently measuring on input A. Selected to B would mean it would trigger the display on a signal on B (which might be useful if you wanted to see what was happening on input A, every time input B did something). EXT just means you can inject a third signal on the EXT connector, but you wont see it on the screen.
Lots more to discuss about scopes, but thats probably enough to be going on with
Please, ask questions
To me, a scope is the single most important tool this side of a screwdriver, but it is a tool and can tell you what you want to see if you dont use it and understand it.
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